Stapler



FIG. 1 is a perspective view of the front, left and top of a stapler according to a first embodiment showing our new design;

FIG. 2 is a front view thereof, with the rear view being a mirror image thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom view thereof.

The broken lines shown in the drawings form no part of the claimed design. 

The ornamental design for a stapler, as shown and described. 